Ptolemy (c.100–168)

Greek astronomer, mathematician, and geographer, also known as Claudius
Ptolemaeus, who worked at the great library in Alexandria and based his
astronomy on the belief that all heavenly bodies revolve around Earth (see
Ptolemaic system). He authored a 13-volume
work called Mathematical Syntaxis, better known by its later Arabic
name, the Almagest, which is a compendium
of the astronomical works of Hipparchus,
Aristotle, and others, and represents
the most complete description of the Universe as it was then understood.
The Almagest includes a star catalogue containing 48 constellations,
using the names we still use today. Although no longer in serious use, the
catalogue lists 1,022 stars visible from Alexandria and was used as a standard
in the Western and Arab worlds for over a thousand years. An even earlier
star catalogue was that of Timocharis of Alexandria, written in about 300
BC. and later used by Hipparchus. Ptolemy's work promulgated
a sophisticated version of the Aristotelian, geocentric theory which held
sway in the west until the Copernican
Revolution.